Workers from Ukraine's Emergencies Ministry have explored 18 square km of a total 25 square km of the site where a Malaysian airliner crashed and have found 186 bodies, its spokesman, Andriy Lysenko, said.

"The area that needs to be checked stands at 25 square km. Eighteen square km have already been checked," he told a news conference.

"The fighters have allowed Emergencies Ministry workers in there, but they do not allow them to take anything from the area. The fighters are taking away all that has been found."

Meanwhile, walking around the crash site of the ill-fated MH17, freelance photojournalist Filip Warwick witnessed the lives of nearly 300 victims frozen in time.

"I saw one or two passengers still strapped into their seats," he told Fairfax Media from Donetsk province, the epicentre of the pro-Russian movement and the region in which the Malaysia Airlines flight fell.

"So many bodies are beyond recognition, and then there are one or two with barely a scratch and then other cases just bones."

While Ukraine has invited international aviation representatives to assist with the investigation of the MH17 crash, actually getting those representatives to the site is a separate challenge, said Warwick.

"They can arrive to Kiev, but it's another matter altogether of having them actually access the site itself," he said.

"In terms of the area itself there are a number of checkpoints. Even to get here from Donetsk itself you have to go through six or seven checkpoints."

Warwick's arrival at the scene came in the first few hours before there was any security presence, and he believes he saw strong evidence that looting was already well underway.

"I noticed that I hadn't come across a single wallet with money, or a mobile phone or a camera. They've all mysteriously gone missing."

Among the shocks for Warwick was the almost complete lack of official presence or signs of investigation, noting: "The place hadn’t yet been roped off."

When he arrived he said villagers, locals and journalists were walking around stepping on wings and over the wreckage.

Speaking with Fairfax Media more than 24 hours after a surface-to-air-missile struck flight MH17, he noted the absence of organised disaster recovery procedures, such as a "grid".

"The grid is to make sure you have nothing left uncovered. You would use a grid to make marks of the location and you would also mark the various pieces of evidence on the ground," he said.

"So a body would be marked in a particular colour, personal items given a particular colour and plane parts a particular colour. This is standard procedure for any crime scene and this is missing as we speak."

Warwick said he believed the absence of such protocols suggested that those on the ground lacked "the know-how" in dealing with such circumstances.

He reported that a group of 10 separatist soldiers were situated slightly off from the crash site, but "they weren't interacting with anyone and there wasn't anyone interacting with them.

"The only people you could talk to are the emergency services, who are looking for bodies and they won't comment," he said.

Local miners, firemen, fathers and sons have all been seen in the crash area, where bodies are being marked by sticks with white ribbons.

LOOTING, CHAOS

Adviser to the Ukrainian Minister of Internal Affairs, Anton Gerashchenko had earlier reported that "terrorists" have begun collecting valuables belonging to the victims of the tragedy.

"Death-hunters collecting Were not Only Cash money and Jewelry of the crashed Boing passengers died but Also the credit cards of the Victims [sic]," he wrote on his Facebook page.

The reports come alongside those of a chaotic investigation being conducted among the wheat fields at the crash site.

All 283 passengers, and 15 crew members aboard the Amsterdam-to-Kuala Lumpur flight were killed in Thursday's crash. US authorities and aviation experts say the Boeing 777 was likely brought down by a ground-to-air missile, but so far there is no proof of who fired it. Ukraine and the insurgents blame each other.

Under international civil aviation rules, Ukraine should take the lead in investigating an airline accident on its territory. Anton Gerashenko, an adviser to Ukraine's interior minister, told The Associated Press that the investigation would be carried out by the Interior Ministry and the Security Services of Ukraine, who would work alongside international observers.

European Union officials said Friday that Ukraine has first claim on the plane's two black boxes - a flight data recorder and a cockpit voice recorder - which could contain valuable clues about what happened in the moments before the crash.

An assistant to the insurgency's military commander said Friday that rebels had recovered multiple devices from the wreckage and were considering what to do with them, raising fears they could be headed to Moscow. But Russian Foreign Minister Sergey Lavrov said Russia had no intention of getting hold of the boxes, and insurgent leader Aleksandr Borodai later contradicted his colleague and said the rebels don't have them anyway.

Michael Bociurkiw, spokesman for the Organisation for Security and Co-operation in Europe’s special monitoring mission for Ukraine, told ABC News Radio that bodies at the crash site were already “starting to decompose in the fields”.

''It is astonishing to go there and this scene with no recovery going on,'' Mr Bociukiw said.

Questions remained about how many bodies were there and the location of the black box. Mr Bociukiw's delegation needed to find out whether it was safe enough for international experts to begin their investigation into the disaster. He said many of the separatists appeared ''very aggressive'', under the influence of alcohol and possibly drugs.

He said his team had been in touch with Malaysian senior officials whose prime concern was that the bodies were treated in a human way.

''One immediate requirement would be refrigerated trailers - anything where these bodies could be moved - so they don't continue to lie there, exposed to the elements,'' Mr Bociurkiw said.

He said, 25 workers from the OSCE had access to the crash site for just 75 minutes before they were forced to leave. He said a gun shot was fired into the air as they left.

The UN Security Council on Friday called for "a full, thorough and independent international investigation" into the downing of the plane, but that is a complicated proposition.

OSCE council chairman, Thomas Greminger told Reuters that workers assessing the scene "did not have the kind of access that they expected. They did not have the freedom of movement that they need to do their job. The crash site is not sealed off".

Denjen Doroschenko, an Australian journalist working in Ukraine told Fairfax Media in a radio interview that separatist organisations on the ground were "clueless about how to control a disaster area at all".

Dr Geoff Dell, an air crash investigation expert from Central Queensland University, said in any crash investigation it is critical that all on site know what they are doing.

"The longer it stays unexamined the more likely it gets contaminated, especially when there is people that aren’t really familiar with accident scenes, stomping all over it," he said.

"The longer that goes on the more likely something you’re looking for is either destroyed, or stolen."

He referred to Lauda Air Flight 004 which crashed in Thailand in 1991, in which a critical component was never found due to looting.

"Overnight a large percentage of the wreckage was pilfered. Pieces of the airplane that you couldn’t for the life of you think someone would want to steal, were taken," he said.

Dr Dell said it was crucial that proper protocols were followed, such as protecting the perimeter to keep people out and setting up a grid.

"You draw up a grid so you can set up the relationship with the wreckage and identify exactly where each critical piece of evidence came from," he said.

Armed guards are reportedly guarding the crash site near Torez, in a remote eastern area of Ukraine, where it is said the typical investigation grid is absent.

Dr Dell said bodies that are still at the scene pose a different risk, as the risk of infection and disease to investigators on the crash scene increases.

"It's inevitable some contamination will take place during the rescue of removal of the bodies," he said.

"In other parts of the world there is less awareness of that, and I wouldn't be surprised given what we’ve seen, if the crash site hasn't already been substantially altered by the actions of the people in the first response."

WHAT HAPPENED TO MH17?

To figure out why a Malaysian jetliner fell from the sky, investigators will use the wreckage of any missile found to determine where it came from and who fired it, experts say. That may be easier said than done in the middle of a war zone, in which both sides have interests that may outweigh a desire to uncover the truth.

"We are in a country that is at war, and that is in a war of communication," aviation analyst Gerard Feldzer said in Paris.

"Everyone is pushing a pawn."

Foreign Affairs Minister Murray McCully said a New Zealand woman on the plane normally resided in Australia, and was travelling with her husband, a Dutch citizen. A British citizen also on the plane had lived in New Zealand long-term.

Two Newcastle United fans who were travelling to watch their football team play in New Zealand were among the victims.

John Alder, known to fans as "The Undertaker", was on MH17 alongside fellow Magpies fan Liam Sweeney, 28.

Alder, believed to be in his 60s, was well-known among Newcastle fans for always wearing a suit to games. He was also known for his mullet-style haircut.

The former British Telecom worker had only ever missed one game since 1973 and travelled to every away match.

The US ambassador to the United Nations, Samantha Power, said Washington believed the plane was likely downed by an SA-11 missile fired from an area controlled by pro-Russian separatists. She said Russia has provided the militants with SA-11s and other heavy weapons.Defence experts said the plane was likely shot down by a missile fired from a Buk system, Soviet-era equipment that is in the arsenals of both Russia and Ukraine. There was no previous evidence of separatist rebels using such missiles, though a rebel Twitter account boasted last month about seizing a Buk system from Ukrainian forces, and AP journalists saw such a system hours before the crash in rebel-held territory.

Feldzer, the air-accident expert, said investigators' goal would be to "find the debris of the missile in question and determine the trajectory". Once investigators reach the site, they should be able to discover whether the plane was hit by one or more missiles, and the size of the missile system involved.

But, he said, "that won't determine who did it", unless investigators can find a satellite photo or radar records of the missile.

Justin Bronk, a research analyst at the Royal United Services Institute, a London-based military think tank, said the United States has sophisticated military satellites capable of detecting a missile launch, but might be unwilling to share its images in order to protect its secret surveillance capabilities.

"They will probably try to liaise with civilian satellite operators to see if there are any who also picked up the trail on infra-red sensors so that they can publicly release that data," he said.

Charles Heyman, editor of Armed Forces of the EU, said missile casings could help establish who had supplied the weapons that brought down the plane. But he said it was likely that the rebels - if they fired the missile - would have removed any missile-casing debris from the scene.

Heyman said the missile launcher would bear ID numbers that could establish whether it was recently supplied by Russia or came from Ukrainian forces.

But he said if rebels mistakenly targeted a commercial airliner, thinking it was a Ukrainian military plane, they may have subsequently fled and taken the missile launcher into Russia.

The Ukrainian Interior Ministry released video purporting to show exactly that: a truck carrying a Buk missile launcher with one of its four missiles apparently missing, rolling toward the Russian border. The ministry said the footage was captured by a police surveillance squad at dawn Friday. There was no way to independently verify that claim.

"If I was the rebel chief of staff, I'd have had it taken away, dismantled and blown up," Heyman said, "and then bury the pieces in a swamp".

NATIONALITIES OF PASSENGERS ON MH17:

* Netherlands - 192 (including 1 dual Netherlands/USA citizen)

* Malaysia - 44 (including 15 crew, 2 infants)

* Australia - 28 is the official federal government figure, although the airline puts it at 27